* VB-CODE (1)
Tip 147: Retrieving Multiple File Names from the Common Dialog Control

August 31, 1995

Abstract
The Common Dialog File control lets you easily select one or more files
in your Microsoft? Visual Basic? application. This article shows how you
can retrieve the names of selected files from the Common Dialog control.

Using the Common Dialog Control
The Common Dialog File control in Microsoft? Visual Basic? allows you to
provide a user with access to the directory and file structure of the hard
disk from within an application. For example, if a user needs to select a
text file, you can display a Common Dialog File control box that allows
that user to browse various directories until he or she finds the needed
file.

By setting the Flags property of the Common Dialog control to the constant
value OFN_ALLOWMULTISELECT, you can make it possible for your user to
select several files to work with. Multiple files can be selected by
clicking each file name while pressing and holding down SHIFT or CTRL.
The selected file names are highlighted.
To enable your Visual Basic program to work with files selected by the
user, you need to retrieve each file name from the control's Filename
property. The file names selected by the user are all stored in this
property as one long string. Each file name is separated by a space (32)
character.

You can use the InStr function to search for the delimiting space
character to retrieve each file name from the Filename property of
the Common Dialog. The InStr function returns the location of the
space character within the Filename property string. After you have
obtained the location of the space character, you can use the Mid
function to remove the individual file name entry from the string.

Example Program
This program shows how to retrieve all file names selected in a Common
Dialog File control.

 1. Create a new project in Visual Basic. Form1 is created by default.
 2. Add a Common Dialog control to Form1. CommonDialog1 is created by
    default.
 3. Add a Text Box control to Form1. Text1 is created by default.
 4. Add a second Text Box control to Form1. Text2 is created by default.
    Set its MultiLine property to True.
 5. Add a Command Button control to Form1. Command1 is created by default.
 6. Add the following code to the Click event for Command1:

Private Sub Command1_Click()
    Dim I As Integer
    Dim Y As Integer
    Dim Z As Integer
    Dim FileNames$()
 
    Const OFN_ALLOWMULTISELECT = &H200&
 
    CommonDialog1.filename = ""
    CommonDialog1.Filter = "All Files|*.*"
    CommonDialog1.Flags = OFN_ALLOWMULTISELECT
    CommonDialog1.Action = 1
    CommonDialog1.filename = CommonDialog1.filename & Chr(32)

    Z = 1
    For I = 1 To Len(CommonDialog1.filename)
        I = InStr(Z, CommonDialog1.filename, Chr(32))
        If I = 0 Then Exit For
        ReDim Preserve FileNames(Y)
        FileNames(Y) = Mid(CommonDialog1.filename, Z, I - Z)
        Z = I + 1
        Y = Y + 1
    Next
 
    If Y = 1 Then
        Text1.Text = FileNames(0)
    Else
        Text2.Text = ""
        For I = 0 To Y - 1
            If I = 0 Then
                Text1.Text = FileNames(I)
            Else
                Text2.Text = Text2.Text & UCase(FileNames(I)) & Chr$(13) & Chr$(10)
            End If
        Next
    End If
End Sub

Run the example program by pressing F5. Click the Command Button. The
Common Dialog Box File control will be displayed on the screen. Then,
select several files from the file list by clicking a file name while
pressing and holding down SHIFT or CTRL. After you have selected he
appropriate file(s), click OK. The file names will be displayed in the
second Text Box control, and the directory name will be displayed in the
first Text Box control.

Additional References
"Common Dialog Control." (Development Library, Product Documentation,
   SDKs, Win32 SDK, Win32 Programmer's Reference, Window Management,
   System Services